|The MGA With An Attitude
BALL JOINT Length and Cross Reference List - SR-109A
Steering tie rod ends lead a rough life on the MGA, down close to the road with lots of mechanical agitation while driving. Over time they they may lose a grease seal, wear out, and need replacement. These parts will have a better chance for long term survival if they have a grease fitting (as original) for attention with periodic chassis lubrication.
Click for larger picture. Notice under the 90 degree grease fitting there is a thin steel cup washer and a fiber washer. Under the metal cup washer there is a shallow slot in the ball housing (just visible at edge of the metal washer). This slot connects with a small vent hole. Purpose of this arrangement is to allow grease to escape if too much grease is injected during lubrication, so it doesn't blow off the rubber boot. This also assures that the joint is full of grease to exclude any infiltration of water, and it may help maintain integrity of lubrication for a while longer if the rubber boot might be damaged.
Early production MGA did not have the vent hole in the ball housing. The ball joint design was changed beginning at (c)55545 RHD and (c)55875 LHD. Earlier ball joints can be modified to match the later parts using a Belville spring cup washer and a special fiber washer. The fiber washer has a shoulder with small pilot diameter extension within the ID of the cup washer. This shoulder controls exact amount of compression of the cup washer to maintain the vent space underneath. The pliable fiber washer also allows indexing (orientation) of the 90-degree grease fitting to point forward and inboard for convenience of lubrication. Refer to Confidential Service Memorandum MG-229 and MG-233 for details of this design change and possible modification.
I have driven my MGA long enough to appreciate that this ball joint should have a grease fitting. The original tie rod ends with greaser lasted about a quarter million miles, and I believe they only wore out after the rubber boot failed. The replacement parts without a greaser lasted about 100,000 miles before one of them was shot, and no way to save it without any facility for re-lubrication. Some common replacement parts from many well known British car parts suppliers may have no grease fitting (as well as being too long and needing to be modified during installation). "Lubed for life" only means the life ends when the lubrication fails, and you then get to throw it away and buy another one (plus cost and inconvenience of installation). My new replacements are definitely going to have a grease fitting, as well as being the correct size so not to need modification (even if I have to pay a little more for them).
Steering tie rod end for all MGA
Socket assembly - ball ACH6168 J29
| Boot (rubber) 7H3571 J30
| Clip for boot 7H3565 J31
| Ring for boot clip ACA6004 J32
| Washer for ball socket PWZ107 J33 Plain Washer 7/16
| Nut for ball socket FNZ407 J34 Flat Nut 7/16-20
| Lubricator for ball socket UHN405 J36
| Washer for lubricator (dished) ACH6170 J37
| Washer for lubricator (fibre) ACH6173 J38
Following is a reference list of part numbers for this ball end from various sources. Local auto parts stores may cross feference toa different part number (or to their own company part number). For the parts that are too long you may refer to special instructions for modification of the part before installation. The Beck/Arnley part is widely available on line. Put any of these part numbers into an internet search engine.
Applications list: (surely not all inclusive)
BMC MGA (SPL) ACH6168
Borg & Beck BTR4004 (may be too long)?
EAN 50 12759 85140 1
First Line FTR4004 (may be too long)?
MG Parts UK BEK040 (may be too long)?
Monroe L0290 (may be too long)?
Moss Motors US 263-288 (pr) (definitely too long, no zerk)
Quinton Hazell QR290S (no zerk)?
Quinton Hazell QR290PR (no zerk)?
Triscan 8500 290 (may be too long)?
Victoria British 5-105 (pr) (definitely too long, no zerk)
Austin Healey Sprite Mk1 (Bugeye), Mk2, Mk3: 1958-1971
MG Midget Mk1, Mk2, Mk3: 1961-early 1972 (up to car# GAN5/114642)
MGA: 1955-1962 (All models)
MG Magnette ZA: 1956 Only
MG Magnette ZB: 1957-1958
Morris Minor 1000: 1959-1971
Morris Oxford, Cowley, Isis: 1955-1959